Within the spine, the intervertebral disc functions to stabilize and distribute forces between vertebral bodies. It comprises a nucleus pulposus which is surrounded and confined by the annulus fibrosis.
Intervertebral discs are prone to injury and degeneration. For example, herniated discs typically occur when normal wear or exceptional strain causes a disc to rupture. Degenerative disc disease typically results from the normal aging process, in which the tissue gradually loses its natural water and elasticity, causing the degenerated disc to shrink and possibly rupture. Intervertebral disc injuries and degeneration may be treated by fusion of adjacent vertebral bodies or by replacing the intervertebral disc with an implant, also known as a prosthesis or prosthetic device. Generally, fusion of the adjacent vertebral bodies prevents movement between the adjacent vertebrae and the range of motion provided by the natural intervertebral disc. Some implants, on the other hand, preserve at least some of the range of motion provided by the natural intervertebral disc.
Although existing devices and methods associated with intervertebral implants have been generally adequate for their intended purposes, they have not been entirely satisfactory in all respects. The devices and methods in this disclosure overcome one or more of the shortcomings of the prior art.